If at least 2 of the 3 participants with 48-hour intervals respond (defined as a significant within-subject increase in cell-associated HIV RNA), then 3 subsequent participants will receive 48-hour intervals. If 2 of these 3 respond (4 of 6 total), then 3 additional participants will receive 48-hour intervals. If among the first 6 evaluable participants receiving 48-hour intervals there are 3 non-responders, then subsequent participants will receive 72-hour intervals. Participants receiving 72-hour intervals will then be assessed in the same way as those receiving 48-hour intervals, to either continue additional participants at 72-hour intervals or to increase to 96-hour intervals. Step 3 will enroll until a total of 12 evaluable subjects with a measureable increase in cell-associated HIV RNA are obtained, and these participants have advanced to Step 4.